The present invention relates to an optical disk drive, also referred to herein as simply a disk drive, for recording a data signal and/or reproducing a data signal recorded to an optical disk, also referred to herein as simply a disc, used as a data storage medium. A Compact Disc or CD is exemplary of such data storage media.
A disk drive typical of those related to the present invention has an opening on the front panel through which a disk tray opens and closes. After the tray is opened and a disk is loaded onto the tray, the tray is automatically closed, that is, retracted into the disk drive to a turntable.
When a disk is loaded into this type of disk drive it is held between the turntable and a clamp and driven at a specific rotational speed so that data signals recorded to the disk can be read by the disk drive, that is recording or reproducing apparatus, during a read operation, for example. More specifically, signals are recorded to tracks within a specific area of the disk, and an optical pickup for signal reading is driven according to the track address of the desired signal so that the desired signal can be reproduced.
This type of disk drive has three basic operations that require drive motor power: (1) disk loading whereby the tray is driven in two directions between a disk loading/unloading position outside the disk drive at which a disk can be placed on or removed from the tray, and a loading/unloading position inside the disk drive at which the disk is loaded to or unloaded from the turntable; (2) disk driving whereby the turntable is driven to spin a disk; and (3) pickup driving whereby an optical pickup is driven primarily between positions at the outside circumference and inside circumference of the disk.
Typical disk drives according to the related art have also used separate motors, that is, three individual motors, as the drive source for these three operations.
This problem of needing three motors was partially addressed by a disk player (disk drive) as taught in Japanese Utility Model Laid-Open Publication No. 3-49682. This disk player reduced the number of required motors to two, that is, driving a single loading motor in forward and reverse directions for disk loading and unloading, disk chucking, and pickup drive.
A disk drive according to the related art typically comprises a case and a chassis essentially integrated with the case, a turntable fixed to the chassis, and the drive motors. That is, because the vertical position of the turntable is fixed, the disk must be moved vertically for disk loading and unloading in order to avoid interference with the turntable. In addition, the clamping means (chucking plate) must be driven vertically in order to clamp the disk to the turntable.
A disk holder for lifting the disk is therefore provided at the disk holding surface of the tray in a conventional disk drive. The disk holder is then rotated up or down timed to the tray movement so as to avoid interference between the disk and turntable during disk loading and unloading. A chucking plate is further provided supported by a chucking arm on the fixed chassis so that the chucking plate can rotate and move vertically. This chucking plate is rotated up or down according to the disk loading and unloading timing to either clamp the disk to the turntable or to release the disk. Drive construction and operating the component parts are thus quite complicated and disadvantageous with respect to simplifying drive construction and achieving good stable operation.
Furthermore, all drive parts other than the tray and associated drive system are also provided on the fixed chassis in this conventional disk drive. In addition, these parts are rigidly attached or supported on the fixed chassis. As a result, any impact, shock, or vibration to which the disk player is exposed is also transmitted directly from the fixed chassis to the various rigidly attached drive parts. These parts are thus easily susceptible to major damage. This design is therefore disadvantageous with respect to improving the durability of the disk drive to the effects of external forces, that is, resistance to shock and vibration.
Rigid attachment of these components to the fixed chassis also makes it necessary to extremely precisely position these components relative to each other. Extremely high precision is therefore required in both parts manufacture and assembly. When the need to mass produce these components is considered, this need for extremely high precision is disadvantageous with respect to increasing productivity.
Considering these problems of the related art, the basic object of the present invention is therefore to provide an optical disk drive whereby the number of motors used can be reduced, construction can be simplified, durability and resistance to shock and vibration can be improved, and productivity can be improved in mass production.